A surgical system that is able to sense the onset of an occlusion or other surgical event as well as when an occlusion breaks. To help avoid overheating of the tip, the system of the present invention predicts the temperature of the eye using irrigation flow rate and reduces the power to the handpiece automatically if an overheating situation is predicted. Alternatively or in addition, the system of the present invention monitors the power drawn by the handpiece, which is indicative of the cutting load on the tip, and automatically adjusts the power or stroke of the tip to compensate for increased loads on the tip.